Sloping transportation apparatus for carrying large sized objects

ABSTRACT

A sloping transportation apparatus in which a step for carrying a large-sized object periodically appears without requiring any successive operation and which yet constitutes no hindrance to ordinary passengers&#39; standing, ascent or descent. An enlarged step, of which the tread face has a run large enough to place a large-sized object such as a wheelchair thereon, is preceded and followed by at least one reduced step having a tread face with a reduced run (where ordinary steps have a run of 400 mm, 500 mm or 600 mm, the enlarged step is preceded and followed by three, two or one reduced step, respectively), to absorb the excess of the run of the enlarged step so that the steps may be equally joined in a horizontal straight traveling section. Also, a step structure for coupling each tread face to supporting rollers is provided. An auxiliary wheel is additionally provided to reinforce the support for the enlarged step, and the shape of a step guide surface is determined such that the steps do not interfere with peripheral parts in a turning section. The structure is applicable to an apparatus of the type in which the steps circulate in two ways with horizontal orientation of the tread faces thereof maintained throughout the entire traveling course. The enlarged tread face may have a recess formed therein as a wheel stopper for receiving the ground-touching portions of wheels.

TECHNICAL FIELD

The present invention relates to a sloping transportation apparatusincluding an escalator, which has a step with an integral tread facepermitting a large-sized object such as a wheelchair or large-sizedbaggage to be placed thereon and which is installed as a publicpassageway or in works to thereby contribute welfare and convenience.

BACKGROUND ART

Various types of escalators capable of carrying a large-sized objectsuch as a wheelchair have already been developed and put to practicaluse. All of these types of escalators look like an ordinary escalator inappearance but are provided with mechanisms for transforming a specialgroup of steps into a level surface when it is necessary to transportthe large sized object and an attendant's help is necessary foroperating the mechanism and placing the object. Accordingly, ordinaryusers are excluded and it is necessary that the traveling operation besuspended for a considerably long time, giving rise to a problem thatordinary users have to endure inconvenience. In addition, the escalatorsof the aforementioned types are generally complicated in structure andcostly. Further, a rise of the wheelchair carrying step is twice orthree times as large as that of an ordinary rise, thus impedingpassengers' steps. There has also been proposed an escalator capable ofcarrying a large-sized object, in which separate tracks are providedindividually for one or two additional steps added to an ordinary stepso as to form a step for carrying a large-sized object and for anintermediate step intervening between an ordinary step and theadditional step, thereby eliminating the need for the transformationmechanism. Because of an increased number of tracks, however, it isdifficult to put this type of escalator into practical use. Meanwhile, awheel stopper conventionally used is a retractable type.

DISCLOSURE OF INVENTION

The present invention provides a sloping transportation apparatusincluding an escalator, which is capable of carrying a large-sizedobject without requiring a complicated transformation mechanism unlikeconventional escalators for carrying a wheelchair and without the needof a large number of separate tracks, simple in structure and cancurtail the labor and time associated with operation.

Tracks employed in the invention, on which the steps travel, are similarto those to which steps of identical size are coupled, and at least onereduced step with a reduced run is connected before and behind anenlarged step having a single tread face permitting a large-sized objectto be placed thereon. A step group have suitably varied shapes anddimensions, and no special manipulation is required substantially exceptfor the operation of a wheel stopper mechanism. During travelingoperation, the group of steps including the enlarged step capable ofcarrying a large-sized object such as a wheelchair on its singleenlarged tread face appears periodically. Provided the ran of theenlarged step is A and the run of ordinary steps is AO, then an excessof the run of the enlarged step is A-AO. At least one adjacent steppreceding and succeeding the enlarged step has a reduced run so that thesteps may be equally joined in a horizontal traveling section. Thereduced run is set not to cause a passenger any inconvenience, and thereduced steps should preferably be small in number. The aforementionedexcess of the run of the enlarged step may be equally divided betweenthe adjacent reduced steps preceding and succeeding the enlarged step,and in this case a reduction X of the run required of each reduced stepis (A-AO)/2. For simplicity's sake, approximate numerical values will begiven as respective dimensions in the following description. Thefollowing describes cases where the invention is applied to an escalatorof conventional type in which steps are reversed during circulation andthe run A of the enlarged step is set to 1200 mm so that a large-sizedmotorized wheelchair can be placed thereon.

(I): In the case where the run AO of the tread faces of ordinary stepsis set to 400 mm.

The excess of the run of the enlarged step is 1200-400=800 mm, andaccordingly, the required reduction of the run of the preceding andsucceeding steps is 400 mm each. The required reduction of run may bedivided in various ways, and one of the best methods will be to dividethe required reduction into 150 mm, 100 mm and 150 mm such that adjacentthree tread faces have runs of 250 mm, 300 mm and 250 mm, respectively.If the angle α of inclination of the escalator is 30°, rise H=AOsinα=400×0.5=200 mm, where AO=step pitch.

(II): In the case where the run AO of the tread faces of ordinary stepsis set to 500 mm.

The excess of the run to be absorbed by each side of the enlarged stepis (1200-500)/2=350 mm. This required reduction is divided equallybetween two adjacent runs, then the run of each reduced tread face is500-350/2=325 mm, which is a dimension fit for practical use. If α is30°, the rise H is 250 mm, which is thought to be within an allowablelimit, and if α=23°35', then H=200 mm.

(III): In the case where the run AO of the tread faces of ordinary stepsis set to 600 mm.

The reduction of the run required of each side is (1200-600)/2=300 mm,and thus if one reduced tread face is provided on each side of theenlarged step, the run of each reduced tread face is 600-300=300 mm,ensuring a sufficiently practical use. If α is 30°, the rise H is 300mm, which is somewhat too large; therefore, if α is set to 25°, H600×0.4226183 =253.57 mm, which generally falls within the allowablelimit.

As seen from the above-described cases, it is possible to provide anescalator that does not cause passengers any inconvenience, but toattain this, consideration must be given to the following. First, thenumber of rollers for supporting the enlarged step with a large weightneeds to be increased. Second, the escalator must be constructed suchthat interference of the steps is never caused under the floor in aturning section. To meet this requirement, a curved section with aradius of curvature considerably greater than the radius of a drivinggear is provided between the horizontal traveling section and thedriving gear, thereby preventing interference of the steps under thefloor. Third, since the positions of the tread faces are shifted fromthe positions of corresponding supporting rollers, the structure of thesteps needs to be determined such that the steps never interfere witheach other and also have sufficient strength. Fourth, a wheel receivingrecess is formed on the enlarged step so that it may serve as amanipulation-free wheel stopper.

By taking the above into consideration, it is possible to produce anescalator of which the tread face are properly joined in the horizontaltraveling section and never undergo interference under the floor in theturning section and which also has sufficiently high supportingcapability. Escalators can be classified into the conventional type inwhich the train of steps is reversed at the turning section and thentravels on the hidden side of the escalator to return to the originalposition, and a type in which two ways, forward and backward, areconstituted by a series of steps (an escalator whose tread facesmaintain their horizontal orientation throughout the entire travelingcourse is an apt example). In the following, such escalators will bedescribed in detail along with the structure and function of themanipulation-free wheel stopper.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a side view of a sloping transportation apparatus of treadface reversal and circulation type of which the run of tread faces isset to 400 mm;

FIG. 2a is a side view showing a turning section with intervening arcs,and FIG. 2b is a side view showing a turning section with no interveningarcs;

FIG. 3a is a side view showing external forms of steps of a slopingtransportation apparatus of horizontal orientation maintenance andcirculation type, and FIG. 3b is a side view showing part of stepsequipped with a parallel link mechanism and a guiding mechanism;

FIG. 4 is a plan view showing intervening curves at a turnaroundsection;

FIG. 5a is a side view showing an arcuate recess formed as a wheelstopper on an enlarged tread face of a transportation apparatus of treadface reversal and circulation type, FIG. 5b is a side view showingarcuate recesses as a wheel stopper of a transportation apparatus ofhorizontal orientation maintenance and circulation type, and FIG. 5c isa plan view of a recess type wheel stopper;

FIGS. 6a to 6d illustrate the relationship between lengthwise grooves ofa tread face and a comb, wherein FIGS. 6a and 6b are a side view and aplan view of a fixed comb, respectively, FIG. 6c is a sectional viewshowing the grooves and the comb, and FIG. 6d is a side view of amovable comb;

FIG. 7 is a side view of a sloping transportation apparatus of treadface reversal and circulation type of which the run of tread faces isset to 500 mm;

FIG. 8 is a side view of a sloping transportation apparatus ofhorizontal orientation maintenance and circulation type of which the runof tread faces is set to 500 mm;

FIG. 9 is a side view of a sloping transportation apparatus of treadface reversal and circulation type of which the run of tread faces isset to 600 mm; and

FIG. 10 is a side view of a sloping transportation apparatus ofhorizontal orientation maintenance and circulation type of which the runof tread faces is set to 600 mm.

BEST MODE OF CARRYING OUT THE INVENTION

Various embodiments of the present invention will be described referringto the drawings. However, for those parts or elements which have noclose relevance to the present invention, illustration and descriptionthereof are omitted or only brief description will be made. Exemplarydimensions are expressed according to the metric system. In the casewhere a roller chain for vessels is used, however, since the dimensionsof the chain are expressed using a basic unit of an inch (about 25.4mm), "25 mm" should be understood to mean "25.4 mm" especially fordimensions of ran etc. of steps.

(1): In the case where the run AO of ordinary tread faces is set to 400mm.

In a sloping straight traveling section, an enlarged step 5 capable ofcarrying a large-sized object such as a wheelchair 100 is situatedbetween a lower group of steps 1, 2, 3 and 4 and an upper group of steps6, 7, 8 and 9, both in ascending order, the steps 1 and 9 have a run of400 mm, the steps 2, 4, 6 and 8 have a run of 250 mm, and the steps 3and 7 have a run of 300 mm. The run 300 mm is large enough for apassenger to stand on the tread face, and the run 250 mm is large enoughfor a passenger to put his/her foot on the tread face when ascending ordescending the steps. The positions of some tread faces are shifted fromthe positions of corresponding supporting rollers, and thus specialmeasures need to be taken for the step structure. Namely, differentstructures are required depending on articulation and driving types.

(1a): In the case of conventional type escalator in which the treadfaces are reversed during circulation.

To prevent part of the steps from interfering with each other, somesteps connecting the respective tread faces to corresponding supportingrollers (step rollers and trailer rollers) have a sectional form suchthat part thereof is elongated and extends beneath another step, asshown in the side view of FIG. 1. When designing this type of escalator,therefore, special care needs to be given to the strength and therigidity. To enable the enlarged step 5 to safely bear a large weight,an auxiliary wheel 53 with high load bearing capacity is provided on theroof of a guide groove associated with at least one of the step roller51 and the trailer roller 52. FIG. 1 illustrates the case where theauxiliary wheel 53 is made to roll on a guide surface 03 of the roof ofa guide groove 01 associated with the step roller 51 (the guide groovefor the step rollers 11, 21, 31, . . . of the respective steps 1, 2, 3,. . . ).

Another problem to be solved is that the enlarged step 5 should notinterfere with the underside of the floor or its peripheral parts at theturning section. As a means to solve the problem, as shown in the sideview of FIG. 2a, curved portions with small curvature, for example,arcuate guide portions 012 having a radius R2 considerably greater thanthe radius R5 of a pitch circle of a chain gear 05, are made tointervene between a horizontal straight traveling section 011 of thestep roller guide groove 01 and an arcuate portion 013 corresponding tothe chain gear 05. FIG. 2a shows that, where R2=2.6R5, the amount k ofprojection of an end portion of the step 5 is smaller than the amount k0of projection observed when no intervening guide portions with smallcurvature are provided as shown in FIG. 2b, whereby the interference ofthe step with the underside of the floor or its peripheral parts can beprevented.

(1b): In the case of escalator in which two ways, forward and backward,are coupled such that the tread faces maintain their horizontalorientation.

The following describes a case where the present invention is applied toan invention (PCT/JP97/03613) with a principal construction whereinsteps are articulated by means of a parallel link mechanism capable offlexing in the centers of coupling links, guide rollers provided onjoint shafts of the flexing sections are guided, and the guide rollersconstitute part of a driving mechanism at a turnaround section. As shownin FIG. 3a, the steps have a somewhat unusual sectional form so thatadjacent steps can be prevented from interfering with each other, and inorder that a similar articulated condition may be restored after thesteps make a turn by 180°, the steps 4 and 6, the steps 3 and 7, and thesteps 2 and 8 are individually symmetrical with each other and astructure shown in FIG. 3b is employed as an internal mechanism. Acolumn 56, which extends downward from a moving handrail at a locationbelow the step 5, is provided with lower and upper pin contacts 57a and57b to be connected to parallel links, supporting rollers 57 and 58 arearranged symmetrically on front and rear sides of the lower pin, and anauxiliary wheel 59 is arranged (with its center located on the centerline of the column 56) such that it rolls on a guide rail 09 provided onthe roof of a guide groove 07 for the front supporting roller 57 (theguide groove for the front supporting rollers 17, 27, 37, . . . of therespective steps 1, 2, 3, . . . ). A supporting roller and an auxiliarywheel are provided also on the outside of the step. It should be notedthat since the direction is reversed in the opposite way after a turn by180°, the positions of the front and rear rollers are reversed.

Thus, the horizontal orientation of the steps is secured doubly by thetwo guide grooves for the supporting rollers and the parallel linkmechanism, and it is especially advantageous that the horizontalorientation of the enlarged step can be maintained. In order to preventthe enlarged step 5 from interfering with its peripheral wall surfaces,a guide surface 078 of the horizontal straight traveling section and aguide surface 09 (radius of turn: R9) of a gear-driven arcuateturnaround section are connected by curves with small curvature (in theexample shown in the figure, arcs 015 with a radius R3), thereby toreduce the value of k' shown in FIG. 4.

(2): In the case where the run AO of ordinary tread faces is set to 500mm.

Currently, the run AO of ordinary tread faces is set to 400 mm, butmainly because of an oppressive feeling that a passenger has whenstanding between passengers, the fact is that the utilization factor ofthe steps is as low as 50 to 75% even during the rush hours. If AO isset to 500 mm, passengers hardly feel oppressed; accordingly, theutilization factor improves and strangeness in shape of the stepsadjacent to the enlarged step lessens. Where the angle a of inclinationof the escalator is set to 30°, the rise H is 250 mm, which is somewhattoo large; however, if α is set to 27°, then H is 227.0 mm, which fallswithin the practically allowable range. The following describesdifferent articulation types.

(2a): In the case of chain-driven type escalator in which the stepsreturn on the hidden side of the escalator.

As shown in the side view of FIG. 7, the steps have relatively moderatesectional forms. The auxiliary wheel and the turning section arebasically identical in shape with those described in (1a) above.

(2b): In the case of escalator of the type in which two ways, forwardand backward, are coupled such that the tread faces maintain theirhorizontal orientation.

Where the steps are basically identical in structure with thosedescribed in (1b) above, their strangeness in sectional form lessens asshown in the side view of FIG. 8. The auxiliary wheels and the guidesurface of the turnaround section are basically identical in structureetc. with those described in (1b).

(3): In the case where the run AO of ordinary tread faces is set to 600mm.

In an airport etc., many passengers carry baggage with them and seldomascend or descend escalators. Thus, even if AO=600 mm and α=30°, theresulting rise H of 300 mm does not constitute a particular hindrance.Since only one reduced step may be provided before and behind theenlarged step, the structure is simplified and also the sectional formsof the enlarged step 5 and its adjacent steps can be simplified. Thefollowing describes different articulation types.

(3a): In the case of chain-driven type escalator in which the stepsreturn on the hidden side of the escalator.

A train of steps including the enlarged step 5 in the middle has asectional form as shown in FIG. 9. The auxiliary wheel and the turningsection are basically identical with those described in (1a) and (2a)above.

(3b): In the case of escalator of the type in which two ways, forwardand backward, are coupled such that the tread faces maintain theirhorizontal orientation.

A train of steps including the enlarged step in the middle has asectional form as shown in FIG. 10. The auxiliary wheels and the guidesurface of the turnaround section are basically identical with thosedescribed in (1b) and (2b) above.

(4) Wheel stopper function:

An escalator for carrying a wheelchair is provided with a wheel stoppermechanism 55 (FIG. 3a), which is retracted when not in use and is pulledout when a wheelchair is placed on the escalator, to prevent thewheelchair from falling. To make the mechanism entirelymanipulation-free, a different method needs to be adopted. As a novelmethod, a recess is formed on the enlarged tread face for receiving theground-touching portions of at least the front or rear wheels of awheelchair. FIGS. 5a to 5c show different structures to cope withvarious types and dimensions of wheelchairs. FIG. 5a is a side view of astructure for use with the conventional chain-driven type, and FIG. 5bis a side view of a structure for use with the horizontal orientationmaintenance and circulation type.

In the case of FIG. 5a, the recess is formed near and edge of the riser,but in the case of FIG. 5b, the recess needs to be formed both on frontand rear sides, because the position of the riser is revered in forwardand backward ways. The case of FIG. 5a will be explained along withexemplary numerical values given as individual dimensions of theenlarged tread face. A horizontal portion 50a extends from the riseredge for a run e (70 mm), and an arcuate portion 50c having a radius R(=200 mm) and a depression f (=60 mm) from the horizontal plane adjoinsthe horizontal portion 50a. The arcuate portion 50c and a horizontalportion with a run e (mm) at the deepest end are connected by a centralhorizontal portion which has a depression h (33 mm) (the reason will beexplained with reference to the case of FIG. 5b) and which has aninclined flat surface (with lengthwise grooves) inclined at an angleδ(=15°).

In the case of FIG. 5b, arcuate portions are formed on front and rearend portions, respectively, so as to be symmetrical with respect to ahorizontal center line on the tread face. Specifically, horizontalportions 50a and 50b each with a run e (=70 mm) are formed at the frontand rear end portions of the enlarged tread face 5, and arcuate portions50c and 50d with a radius R (=200 mm) and a depression f (=60 mm) fromthe horizontal plane adjoin the respective horizontal portions. Ahorizontal portion with a run of 2t is left in the central portion ofthe enlarged tread face 5, and if the central horizontal portion isdepressed by h (=33 mm) in order to mitigate the inclination of thewheelchair whose front or rear wheels are not received in recess thenthe run 2t of the central horizontal portion equals 573.59 mm because##EQU1## Provided the points of intersection of the arc with the endportion and the central horizontal portion of the tread face are C1 andC2, respectively, and the tangential angles of the arc at these pointsare τ1 and τ2, then

    τ1=arccos(R-f) /R=45°34', tanτ1=1.0200(=coefficient of static friction), τ2=arccos(R-f+h) / R=30°07',

and

    tanτ2=0.5801 (=coefficient of static friction).

The coefficient of static friction between the wheelchair tire and thetread face is 0.6 to 1.0 at most. Accordingly, where the tire diameteris 400 mm or less, the tire received in the recess is braked and neverfalls but yet can be moved beyond C2, and where the tire diameterexceeds 400 mm, the tire can be placed stably between C1 and C2(slightly chamfered). The wheel stopper need not be formed over theentire lateral width but may be provided only in regions where the maintires pass, and this is convenient also for ordinary passengers. Theexample shown in FIG. 5c has a tire region T1(=225 mm), a passengerregion P1(=300 mm), a tire region T2(=225 mm) and a passenger regionP2(=300 mm). Thus, the tire region (=300 to 750 mm, left-hand region=right-hand region =525 mm, and accordingly, there is no hindrance tothe placement of various types of wheelchairs or to the passengers'riding, ascent and descent.

(5) Lengthwise grooves of the tread face and a comb.

For the recessed regions (regions T1, T2) formed on the enlarged treadface as the wheel stopper, deep grooves are formed over the entire treadface, and a comb for engagement with the grooves has an elongated shapewith a large height, as shown in FIGS. 6a to 6c. In order to ensuresufficient strength, a pitch U is set to be greater than a pitch V (seeFIG. 5c ) for the-passenger regions P1 and P2. In the case of theexemplary dimensions set forth in (4) above, an angle β of inclinationof a comb 005 is set at 15° corresponding to a design limit, and a depthor height G of the grooves is set to about 62 mm, taking account of thethickness and spacing of distal tooth portions of the comb. In caseswhere the depth of the grooves on ordinary tread faces should be keptsmall, a movable comb 006 shown in FIG. 6d may be used, wherein the comb006 is swingably supported on a horizontal shaft 002 parallel with afloor surface 00, and comb guide rollers 003 located at the distal toothportion of the comb 006 are guided along comb tooth guide surfaces 401,501, 601, etc. (partly omitted in the figure) of the steps 4, 5, 6,etc.; however, this method requires complicated structure and cannot besaid practical.

(6) Operation:

Unlike conventional escalators, the present invention does not require amechanism for transforming the escalator so as to carry a wheelchair,and therefore, except for the switch operation before a wheelchair isplaced, the switch operation for the wheel stopper (this is unnecessaryin the case of the recess type wheel stopper) after the escalator isstopped at a predetermined position, and the switch operation forstarting, no other manipulations are required such as confirmation of apreliminary mechanism for the transformation, confirmation of theresults of the transformation, and the restoration after use, wherebythe cost and time can be saved, safety can be improved, and attendanceof the operator may itself be unnecessary as the case may be. In thetransformation type, the rise at the wheelchair carrying section istwice or three times as large as the normal height, constituting ahindrance to passengers' ascent or descent. However, in the presentinvention, the rise may somewhat increase but does not constitute ahindrance. In cases where most passengers carry baggage with them and donot desire to ascend or descend steps, the magnitude of the rise doesnot cause any problem. Also, an enlarged step can be easily provided ina plurality of regions of an escalator, thus shortening the users'waiting time. Existing transformation type escalators are usuallyprovided with a single enlarged step to prevent the structure frombecoming complicated, and this results in an increase in the waitingtime. According to the present invention, in the case where a pluralityof enlarged steps are arranged at equal intervals, control operation isperformed such that upon depression of a button, a proximity switchsensor closest to an arriving wheelchair is set operative, followed byreduction in speed and then stop of the escalator.

According to the present invention, the enlarged step capable ofcarrying a large-sized object such as a wheelchair automatically andperiodically appears without requiring special operation, and alarge-sized object such as a wheelchair can be carried even in aperfectly manipulation-free fashion. Also, the reduced steps do nothinder ordinary passengers' standing or ascent or descent.

What is claimed is:
 1. A sloping transportation apparatus for carrying alarge-sized object, in which a plurality of steps are connected totravel forward and backward so that tread faces of the individual stepsare kept horizontal at least in a load carrying section, said apparatuscomprising:a plurality of ordinary steps; at least one enlarged stephaving a tread face with a run greater than that of said ordinary stepsand permitting a large-sized object to be placed thereon; and at leastone reduced step having tread face with a run smaller than that of saidordinary steps and connected adjacent to said enlarged step before andbehind said enlarged step, the tread face of said reduced step beingshifted in position from the tread faces of said ordinary steps in asloping traveling section; wherein positions of all of the steps aredetermined such that the tread faces thereof are properly locatedadjacent to each other on an identical plane in a horizontal travelingsection, and curvature of a guide surface connecting a horizontaltraveling guide surface and a pitch surface of a step driving mechanismis determined such that said enlarged step does not interfere with awall surface under floor in a turning section.
 2. A slopingtransportation apparatus according to claim 1, wherein a train of thesteps circulates such that the steps travel on a reverse side afterpassing the turning section and return to an original position.
 3. Asloping transportation apparatus according to claim 1, wherein each ofthe steps circulates in two ways with horizontal orientation of thetread face thereof maintained throughout an entire traveling course,each of the steps being connected to a parallel link mechanism flexibleat centers of coupling links and guided by guide rollers provided onjoint shafts of flexing sections.
 4. A sloping transportation apparatusaccording to any one of claim 1, wherein the tread face of said enlargedstep has a recess formed therein for receiving ground-touching portionsof wheels of a wheelchair.